A server associated with a physical store stores the list prices of items available for purchase at the store, as well as the available promotions and temporary price reductions (TPRs). At manned or self service checkouts, a scanner scans the barcode of an item and the effective price of the scanned item is received from the server. This effective price reflects the list price as well as all effective promotions and TPRs. In some stores, clients can use portable scanning devices, similar to the scanners at the checkouts, to scan items while shopping. In some cases, the same physical server can be associated with multiple stores.
It is also possible to shop at a shopping website. In this case, the customer visits a shopping website and interacts with a web-server to complete purchases. In a chain with a shopping website and one or more physical stores the effective prices and inventory of items at the website may be the same or different than the effective prices and inventory at the physical store(s).
Furthermore, in a chain with more than one physical store, the effective prices of items at one store are not necessarily the same as those at another store. For example, the list prices may vary depending on the location of the store (e.g. more expensive list prices at stores in more expensive neighborhoods), or for example there may be promotions and/or temporary price reductions available only at that store, etc. Similarly the inventory at one store may not necessarily be identical to the inventory at another store, for example due to different shopping population makeups. Therefore the content of the dataset of items associated with one store may be the same as or different than the content of the dataset of items associated with another store.